Caracterização da matéria orgânica leve e manta orgânica em uma topossequência na ilha de Algodoal/Maiandeua-Pa

Abstract

Soil organic matter comprises a wide variety of humic and non-humic compounds, organic blanket, roots, and decomposing organisms. It can be considered a complex composed of plant and animal residues in continuous chemical, physical and biological transformation, giving the soil the characteristics of a dynamic system, being in constant replacement. The present work aims to analyze the production of light organic matter (LOM) in the soil at depths of 0-5 in, 5-10 in, 10-20 in sites on Algodoal Island/Maiandeua, and to relate the production and quantity of this matter to each soil type. The soil and organic matter samples were collected in a 1370 m long toposequence, where the soils were identified as Yellow Pozolic, Hydromorphic Podzol, Alluvial Soil, Sodic Alluvial Soil and Sodic Solonchak. A varied amount in grams of MOL and organic blanket was observed, comprising the following relationship: Blanket: P4> P4A > P6 @ P5 > P5A > P3, MOL: P4 > P4A > P5A > P5 > P3 > P6. With these data, it is possible to observe the oscillation of MOL and organic matter and correlate their respective amounts with the vegetation of the sites in question and the fertility of the soils. The soils studied are of low natural fertility and sandy. P4 is a hydromorphic Podzol under secondary vegetation (capoeira). P3 is a site with a saline soil character, where grasses and mangrove vegetation predominate.